To Port "and Polish" heads...
So we all know that porting is generally a good thing (unless you don't know what you're doing or get carried away). But, once you're done porting the heads, is it really beneficial to "polish" the ports... as in go over them with a fine grit sanding roll to give them a smooth finish?
I've heard that you want to polish the exhaust ports to keep carbon from building up and effectively making your ports smaller, but the intake port you want to leave rough to keep the fuel from sticking to the walls or trickling down into the cylinder. Is this right? And if rough is better for the intake ports, how rough should it be? For instance, if you don't touch a particular part of the port with the grinder, is it best to leave it as-cast, or should it be smoothed slightly with a coarse sanding roll?
I know someone out there has HAD to test before-and-after "polishing" to see if the flowbench sees a benefit, I just want to know what's considered the best thing to do.
'97 F250HD 4x4 460; '85 Ranger, 350hp 289, T5, email@example.com
"If at first the idea is not absurd, then there is no hope for it.” Albert Einstein